In 2007, soon after taking over command of U.S. forces in Iraq, Gen. David Petraeus admitted, “There is no military solution to a problem like that in Iraq.”

Two years later, Gen. Stanley McChrystal echoed those sentiments about Afghanistan: “Provide them an environment in which they can live and work, and they can have protection of the law and they can develop businesses — that’s the real solution.”

We know how to kick in doors and win battles. But we’re again having to relearn how to secure the peace.

How does this relate to Department of Defense budgeting? Simple: If we invest in increasing our civilian capacity in the areas of stabilization and reconstruction, we limit the need to spend billions on war fighting, and we greatly reduce the need to shoehorn the U.S. soldier into the role of nation builder.

The problem we face today is one of imbalance. The Defense Department has an annual budget in the range of $750 billion. Compare that with all diplomatic, civilian efforts — which ring in at $50 billion.

I don’t suggest a wholesale slashing of the defense budget. What I have called for — and what I believe more and more military leaders are calling for — is a rebalance of our war-fighting and peace-building capacities.

There are three obvious roles for diplomatic efforts: before, during and after conflicts.

Before conflicts even begin, a focused civilian effort could be put in motion. The Foreign Service is the most overt option. But a wide range of agencies could also be ramped up with these efforts in mind.

The U.S. Agency for International Development’s efforts toward humanitarian and economic assistance play a major role in rebuilding nations after conflict. But an ounce of prevention is worth a pound of cure. Increase funding for conflict resolution, agriculture support programs and economic growth, and you lose many of the basic causes of conflict.

And let’s look outside the box. Dollar for dollar, the Peace Corps is the single most effective diplomatic tool we have, yet we continue to underfund its operations.

We conduct a legislatively mandated Quadrennial Defense Review, looking ahead to the kinds of challenges we may face and setting priorities for our resources.

Now, under President Barack Obama, we’re seeing, for the first time ever, a Quadrennial Diplomacy and Development Review that examines our diplomatic efforts as well. If we don’t know our tools, it’s tough to make effective use of them.

After conflicts have started, civilian agencies have a vital role to play in reducing their duration — another avenue to enormous savings for the Defense Department.

In October 2008, Congress authorized the creation of the Civilian Response Corps, an idea I spearheaded with Sen. Dick Lugar (R-Ind.) and then-Sen. Joe Biden (D-Del.). Housed within the State Department, the corps is currently made up of 100 active members charged with preparing for and responding to conflict prevention efforts, stabilization and reconstruction.

Active members are ready to deploy within 48 hours and are backed up by an additional 800 federal employees with a wide range of specialties. With experts in areas ranging from agriculture, law enforcement and commerce to courts, engineering and national security, these are the people trained to make and sustain peace.

Why aren’t we investing more in these kinds of interagency initiatives?

Finally, and most noticeably in the Iraq and Afghanistan conflicts, civilian agencies need to play an increased role in post-conflict reconstruction. And they need to do a better job at it.

In every case in which Washington sends its funds abroad for reconstruction efforts, we find contractors. The expertise they bring to these nations is invaluable, but it comes at a steep price. All too often, they remain in a country far too long, impeding the capacity building required to sustain growth and independence.

We see this in Iraq and Afghanistan today. But we also find it in places like Colombia, where the contractors’ continued presence crimps the ability of local economies to grow and limits economic opportunities.

The State Department has only about 6,500 Foreign Service officers, fewer than the number of military band members. USAID has only about 1,000 Foreign Service officers, down from 4,500 a few decades ago.

We’re slowly realizing that the sword alone cannot solve our problems. As Washington begins this rebalancing effort, we need to devote resources to increasing the number of trained experts who know how to deal with international crises.

Agencies like the Civilian Response Corps have the potential to save the Pentagon billions of dollars. We just need the foresight to support them.

Rep. Sam Farr (D-Calif.) is on the House Appropriations Committee and the Subcommittee on Homeland Security.